1) Bilirubin level ≥ 1.5 upper normal limits 2) AST/ALT ≥ 3 UNL or 3) Serum creatinine ≥ 1.5 9. Any patient hospitalized for acute exacerbation of their condition within 2 months of randomization 10. Recent (within the past 1 month) or planned treatment with prohibited medications in the protocol